Flood Insurance Study (FIS) May Not Contain All Data Available Within the Repository
Total Page:16
File Type:pdf, Size:1020Kb
MCCRACKEN COUNTY, KENTUCKY AND INCORPORATED AREA S COMMUNITY COMMUNITY NAME NUMBER PADUCAH, CITY OF 210152 MCCRACKEN COUNTY (UNINCORPORATED AREAS) 210151 McCracken County Effective Date November 2, 2011 Federal Emergency Management Agency FLOOD INSURANCE STUDY NUMBER 21145CV000A NOTICE TO FLOOD INSURANCE STUDY USERS Communities participating in the National Flood Insurance Program (NFIP) have established repositories of flood hazard data for floodplain management and flood insurance purposes. This Flood Insurance Study (FIS) may not contain all data available within the repository. It is advisable to contact the community repository for any additional data. Selected Flood Insurance Rate Map panels for the community contain information that was previously shown separately on the corresponding Flood Boundary and Floodway Map panels (e.g., floodways, cross sections). In addition, former flood hazard zone designations have been changed as follows: Old Zone New Zone A1 through A30 AE V1 through V30 VE B X C X The Federal Emergency Management Agency (FEMA) may revise and republish part or all of this FIS report at any time. In addition, FEMA may revise part of this FIS report by the Letter of Map Revision process, which does not involve republication or redistribution of the FIS report. Therefore, users should consult with community officials and check the Community Map Repository to obtain the most current FIS report components. Initial Countywide FIS Effective Date: November 2, 2011 i TABLE OF CONTENTS Page 1.0 INTRODUCTION 1 1.1 Purpose of Study 1 1.2 Authority and Acknowledgments 1 1.3 Coordination 3 2.0 AREA STUDIED 3 2.1 Scope of Study 3 2.2 Community Description 4 2.3 Principal Flood Problems 5 2.4 Flood Protection Measures 5 3.0 ENGINEERING METHODS 6 3.1 Hydrologic Analyses 6 3.2 Hydraulic Analyses 10 3.3 Vertical Datum 13 4.0 FLOODPLAIN MANAGEMENT APPLICATIONS 14 4.1 Floodplain Boundaries 14 4.2 Floodways 15 5.0 INSURANCE APPLICATION 29 6.0 FLOOD INSURANCE RATE MAP 30 7.0 OTHER STUDIES 32 8.0 LOCATION OF DATA 32 9.0 BIBLIOGRAPHY AND REFERENCES 32 ii TABLE OF CONTENTS (continued) Page FIGURES Figure 1 – Floodway Schematic 16 TABLES Table 1 - Detailed Study Limits 3 Table 2 - Summary of Discharges 7 Table 3 - Manning’s “n” Values 11 Table 4 - Floodway Data 17 Table 5 - Community Map History 31 EXHIBITS Exhibit 1 - Flood Profiles Black Branch Panels 01P- 02P Camp Creek Panels 03P- 06P Champion Creek Panel 07P-09P Crooked Creek Panels 10P- 12P Cross Creek Panels 13P Island Creek Panels 14P- 19P Massac Creek Panels 20P- 25P Middle Fork Massac Creek Panels 26P- 30P Ohio River Panels 31P- 34P Perkins Creek Panels 35P- 38P Tennessee River Panel 39P West Fork Massac Creek Panels 40P- 43P iii FLOOD INSURANCE STUDY MCCRACKEN COUNTY, KENTUCKY AND INCORPORATED AREAS 1.0 INTRODUCTION 1.1 Purpose of Study This Flood Insurance Study (FIS) revises and updates information on the existence and severity of flood hazards in the geographic area of McCracken County, Kentucky; including the City of Paducah and the unincorporated areas of McCracken County (referred to collectively herein as McCracken County), and aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This study has developed flood-risk data for various areas of the community that will be used to establish actuarial flood insurance rates and to assist the community in its efforts to promote sound floodplain management. Minimum floodplain management requirements for participation in the National Flood Insurance Program (NFIP) are set forth in the Code of Federal Regulations at 44 CFR, 60.3. In some states or communities, floodplain management criteria or regulations may exist that are more restrictive or comprehensive than the minimum Federal requirements. In such cases, the more restrictive criteria take precedence, and the State (or other jurisdictional agency) will be able to explain them. The Digital Flood Insurance Rate Map (DFIRM) and FIS Report for this countywide study have been produced in digital format. Flood hazard information was converted to meet the FEMA DFIRM database specifications and Geographic Information System (GIS) format requirements. The flood hazard information was created and is provided in a digital format so that it can be incorporated into a local GIS and be accessed more easily by the community. 1.2 Authority and Acknowledgments The sources of authority for this Flood Insurance Study are the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This FIS was prepared to include the incorporated communities within McCracken County in a countywide format. Information on the authority and acknowledgments for each jurisdiction included in this countywide FIS, as compiled from their previous printed FIS reports, is shown on the following page. 1 City of Paducah The hydrology and hydraulics analyses for this study were performed by Booker Associates, Inc. (the Study Contractor) for the Federal Insurance Administration, under contract number H-4075. This study was completed in January 1978. McCracken County The hydrology and hydraulics analyses for this study (Unincorporated Areas) were performed by Booker Associates, Inc. (the Study Contractor) for the Federal Insurance Administration, under contract number H-4075. This study was completed in February 1978. For this countywide FIS, with the exception of the Black Branch, Camp Creek, Champion Creek, Island Creek, Massac Creek, Middle Fork Massac Creek, Ohio River, Tennessee River and West Fork Massac Creek new hydrologic and hydraulic analyses were prepared for FEMA by AMEC Earth & Environmental, Inc. under Contract No. EMA-2008-CA-5882 and this work was completed in December 2009. Hydrologic and Hydraulic analysis for Black Branch, Camp Creek, Champion Creek, Island Creek, Massac Creek, Middle Fork Massac Creek and West Fork Massac Creek were performed by the Booker Associates, Inc. (the Study Contractor) for the Federal Insurance Administration, under contract number H-4075. A HEC-2 model for the Ohio River was obtained by AMEC from the Louisville district Corps of Engineers (USACE). USACE also provided a HEC-RAS model for the Tennessee River downstream of Kentucky Dam. New detailed hydrologic and hydraulic analyses were performed for Cross Creek, Crooked Creek and Perkins Creek by AMEC Earth & Environmental as part of an update to this flood insurance study. The extents of these analyses are listed in Section 2.0 of this report. Topographic information consisted of Digital Elevation Models produced by using 2-foot contour data provided by McCracken County (Reference 2) for most of the County and 10 meter Digital Elevation Models produced by the U.S Geological Survey (USGS) (Reference 1) for parts of the Ohio River corridor. Planimetric base map information shown on all FIRM panels was derived from multiple sources. Road centerlines, stream centerlines and political boundary files were provided by the Kentucky Geographic Network and additional stream centerlines and areas were downloaded from the National Hydrography Dataset provided by the U.S. Geological Survey. Users of this FIRM should be aware that minor adjustments may have been made to specific base map features. The coordinate system used for the production of this FIRM is State Plane, Lambert Conformal Conic, Kentucky Single Zone 1600, North American Datum of 1983 (NAD 83), GRS 80 spheroid. Corner coordinates shown on the FIRM are in latitude and longitude referenced to the UTM projection, NAD 83. Differences in the datum and spheroid used in the production of FIRMs for adjacent counties 2 may result in slight positional differences in map features at the county boundaries. These differences do not affect the accuracy of information shown on the FIRM. 1.3 Coordination An initial Consultation Coordination Officer’s (CCO) meeting is held with representatives of the communities and the study contractors to explain the nature and purpose of the FIS, and to identify the streams to be studied by detailed methods. A final CCO meeting is held with representatives of the communities, FEMA, and the study contractors to review the results of the study. For this countywide FIS, initial CCO meetings were held on May 27, 2008, and a final CCO meeting was held on February 8, 2010. The initial meetings were attended by representatives of the City of Paducah, McCracken County, AMEC Earth & Environmental Inc. and Kentucky Division of Water (KDOW). All problems raised at that meeting have been addressed. 2.0 AREA STUDIED 2.1 Scope of Study This FIS report covers the geographic area of McCracken County, Kentucky, including the incorporated communities listed in Section 1.1. The areas studied were selected with priority given to all known flood hazards and areas of projected development or proposed construction through April 2009. Flooding caused by overflow of Black Branch, Camp Creek, Champion Creek, Crooked Creek, Cross Creek, Island Creek, Massac Creek, Middle Fork Massac Creek, Ohio River, Perkins Creek, Tennessee River and West Fork Massac Creek were studied in detail. The extent of the streams studied using detailed methods are listed in Table 1. TABLE 1- DETAILED STUDY LIMITS Stream Limits of Detailed Study Black Branch From its confluence with Massac Creek to approximately 120 feet upstream of Buchanan Road. Camp Creek From KY HWY 348 to approximately 2800 feet upstream of The Old Houser Road. Champion Creek From its confluence with Island Creek to approximately 1550 feet upstream of Clark line Road. Crooked Creek From its confluence with Perkins Creek to approximately 430 feet upstream of US HWY 62. 3 Cross Creek From approximately 570 feet downstream of Railroad yard to approximately 340 feet upstream of South 24th Street. Island Creek Approximately 450 feet upstream of its confluence with Tennessee River to approximately 400 feet upstream of Husband Road. Massac Creek From its confluence with Ohio River to approximately 600 feet upstream of Clinton Road.